This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The ribosome channel complex (RCC) of the endoplasmic reticulum (ER) is responsible for the translocation of secretory and resident proteins of the ER and Golgi into the lumen of the ER, while membrane proteins are gated laterally into the plane of the membrane (Johnson and van Waes, 1999). Thus, the RCC is responsible for the proper biogenesis of all membrane proteins in humans. The SecY complex associates with the ribosome to form a protein translocation channel in the bacterial plasma membrane while the Sec61 complex plays a similar role in the endoplasmic reticulum in eukaryotes (Johnson and van Waes, 1999). Both of these channels were studied by Chris Akey's group at BU Medical School in collaboration with Tom Rapoport at Harvard Medical School.